Systems and methods of facilitating manual adjustment of one or more cochlear implant system control parameters

ABSTRACT

An exemplary cochlear system includes a sound processing unit configured to process an audio signal, an implantable cochlear stimulator communicatively coupled to the sound processing unit and configured to apply stimulation representative of the audio signal to a patient via one or more electrodes in accordance with the processing of the audio signal, and a user input facility communicatively coupled to the sound processing unit. The sound processing unit and the implantable cochlear stimulator are configured to operate in accordance with a plurality of control parameters, which may be selectively associated and disassociated with the user input facility in order to facilitate manual adjustment of one or more of the control parameters. Corresponding systems and methods are also disclosed.

RELATED APPLICATIONS

The present application claims priority under 35 U.S.C. §119(e) to U.S.Provisional Patent Application No. 61/148,762 by Aniket Saoji et al.,filed on Jan. 30, 2009, and entitled “Systems and Methods ofFacilitating Manual Adjustment of One or More Cochlear Implant SystemControl Parameters,” the contents of which are hereby incorporated byreference in their entirety.

BACKGROUND

The sense of hearing in human beings involves the use of hair cells inthe cochlea that convert or transduce audio signals into auditory nerveimpulses. Hearing loss, which may be due to many different causes, isgenerally of two types: conductive and sensorineural. Conductive hearingloss occurs when the normal mechanical pathways for sound to reach thehair cells in the cochlea are impeded. These sound pathways may beimpeded, for example, by damage to the auditory ossicles. Conductivehearing loss may often be overcome through the use of conventionalhearing aids that amplify sound so that audio signals can reach the haircells within the cochlea. Some types of conductive hearing loss may alsobe treated by surgical procedures.

Sensorineural hearing loss, on the other hand, is caused by the absenceor destruction of the hair cells in the cochlea which are needed totransduce audio signals into auditory nerve impulses. People who sufferfrom sensorineural hearing loss are unable to derive any benefit fromconventional hearing aid systems.

To overcome sensorineural hearing loss, numerous cochlear implantsystems—or cochlear prosthesis—have been developed. Cochlear implantsystems bypass the hair cells in the cochlea by presenting electricalstimulation directly to the auditory nerve fibers. Direct stimulation ofthe auditory nerve fibers leads to the perception of sound in the brainand at least partial restoration of hearing function.

To facilitate direct stimulation of the auditory nerve fibers, an arrayof electrodes may be implanted in the cochlea. The electrodes form anumber of stimulation channels through which electrical stimulationpulses may be applied directly to auditory nerves within the cochlea. Anaudio signal may then be presented to a patient by translating the audiosignal into a number of electrical stimulation pulses and applying thestimulation pulses directly to auditory nerves within the cochlea viaone or more of the electrodes.

When a cochlear implant system is initially implanted in a patient, itis usually necessary to fit the cochlear implant system to the patient.Such “fitting” includes adjustment of a variety of control parametersgoverning the operation of the cochlear implant system to values thatare most effective and comfortable for the patient. However, it is oftendifficult or impossible to determine optimal values for many controlparameters because they depend on the particular listening environmentin which the patient is located. For example, optimal noise reductionparameters may be different in a noisy listening environment than in aquiet environment.

SUMMARY

An exemplary cochlear system includes a sound processing unit configuredto process an audio signal, an implantable cochlear stimulatorcommunicatively coupled to the sound processing unit and configured toapply stimulation representative of the audio signal to a patient viaone or more electrodes in accordance with the processing of the audiosignal, and a user input facility communicatively coupled to the soundprocessing unit. The sound processing unit and the implantable cochlearstimulator are configured to operate in accordance with a plurality ofcontrol parameters. The user input facility communicatively isconfigured to be initially associated with a first control parameterincluded in the plurality of control parameters in order to facilitatemanual adjustment of the first control parameter. The user inputfacility is further configured to be selectively disassociated with thefirst control parameter and associated with a second control parameterincluded in the plurality of control parameters in order to facilitatemanual adjustment of the second control parameter.

Another exemplary cochlear implant system includes a sound processingunit configured to apply noise reduction to an audio signal inaccordance with a noise reduction parameter, an implantable cochlearstimulator communicatively coupled to the sound processing unit andconfigured to apply stimulation representative of the noise reducedaudio signal to a patient via one or more electrodes, and a user inputfacility communicatively coupled to the sound processing unit andconfigured to facilitate manual adjustment of the noise reductionparameter.

An exemplary method includes 1) processing an audio signal in accordancewith a plurality of control parameters, 2) directing an implantablecochlear stimulator to apply electrical stimulation representative ofthe audio signal to a patient via one or more electrodes, 3) initiallyassociating a user input facility with a first control parameterincluded in the plurality of control parameters in order to facilitatemanual adjustment of the first control parameter, and 4) selectivelydisassociating the user input facility with the first control parameterand associating the user input facility with a second control parameterin order to facilitate manual adjustment of the second controlparameter.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate various embodiments of theprinciples described herein and are a part of the specification. Theillustrated embodiments are merely examples and do not limit the scopeof the disclosure.

FIG. 1 illustrates an exemplary cochlear implant system according toprinciples described herein.

FIG. 2 is a functional block diagram of an exemplary sound processingunit and implantable cochlear stimulator according to principlesdescribed herein.

FIG. 3 illustrates a schematic structure of the human cochleahighlighting elements according to principles described herein.

FIG. 4 illustrates an exemplary configuration of the cochlear implantsystem of FIG. 1 according to principles described herein.

FIG. 5 shows an exemplary implementation of the cochlear implant systemof FIG. 4 according to principles described herein.

FIG. 6 illustrates an alternative implementation of the cochlear implantsystem of FIG. 4 according to principles described herein.

FIG. 7 illustrates an alternative cochlear implant system according toprinciples described herein.

FIG. 8 shows an exemplary implementation of the cochlear implant systemof FIG. 1 wherein the sound processing unit includes a program selectionfacility according to principles described herein.

FIG. 9 illustrates an exemplary implementation of the cochlear implantsystem of FIG. 8 wherein the program selection facility includes aprogram switch at least partially disposed on an outer surface of abehind-the-ear sound processor according to principles described herein.

FIG. 10 illustrates an exemplary noise reduction gain function that maybe used by a noise reduction facility to increase a signal-to-noiseratio within one or more of analysis channels according to principlesdescribed herein.

FIG. 11 illustrates an exemplary method of facilitating manualadjustment of one or more cochlear implant system control parametersaccording to principles described herein.

Throughout the drawings, identical reference numbers designate similar,but not necessarily identical, elements.

DETAILED DESCRIPTION

Systems and methods for facilitating manual adjustment of one or morecontrol parameters governing an operation of a cochlear implant systemare described herein. In some examples, a cochlear implant system mayinclude a sound processing unit configured to process an audio signaland an implantable cochlear stimulator communicatively coupled to thesound processing unit and configured to apply stimulation representativeof the audio signal to a patient via one or more electrodes. The soundprocessing unit and the implantable cochlear stimulator are configuredto operate in accordance with a plurality of control parameters.Exemplary control parameters include, but are not limited to, volumecontrol parameters, noise reduction parameters, microphone sensitivityparameters, microphone direction parameters, pitch parameters, timbreparameters, sound quality parameters, most comfortable current levels(“M levels”), threshold current levels, channel acoustic gainparameters, front and backend dynamic range parameters, current steeringparameters, pulse rate values, pulse width values, frequency parameters,amplitude parameters, waveform parameters, electrode polarity parameters(i.e., anode-cathode assignment), location parameters (i.e., whichelectrode pair or electrode group receives the stimulation current),stimulation type parameters (i.e., monopolar, bipolar, or tripolarstimulation), burst pattern parameters (e.g., burst on time and burstoff time), duty cycle parameters, spectral tilt parameters, filterparameters, and dynamic compression parameters.

In some examples, a user input facility is communicatively coupled to atleast one of the sound processing unit and the implantable cochlearstimulator. The user input facility is configured to be selectivelyassociated with one or more of the control parameters to facilitatemanual adjustment of the one or more of the control parameters. Apatient may use the user input facility to transmit to the soundprocessing unit and/or implantable cochlear stimulator one or morecommands configured to adjust a desired control parameter.

In the following description, for purposes of explanation, numerousspecific details are set forth in order to provide a thoroughunderstanding of the present systems and methods. It will be apparent,however, to one skilled in the art that the present systems and methodsmay be practiced without these specific details. Reference in thespecification to “one embodiment” or “an embodiment” means that aparticular feature, structure, or characteristic described in connectionwith the embodiment is included in at least one embodiment. Theappearance of the phrase “in one embodiment” in various places in thespecification are not necessarily all referring to the same embodiment.

To facilitate an understanding of the methods and systems describedherein, an exemplary cochlear implant system 100 will now be describedin connection with FIG. 1. As shown in FIG. 1, the cochlear implantsystem 100, also referred to herein as a cochlear prosthesis, includesan external sound processor portion 110 and an implanted cochlearstimulation portion 120. The sound processor portion 110 may include asound processing unit 130, a microphone 140, and/or additional circuitryas may serve a particular application. The cochlear stimulation portion120 may include an implantable cochlear stimulator (“ICS”) 150, a lead160 with an array of electrodes 170 disposed thereon, and/or additionalcircuitry as may serve a particular application. It will be recognizedthat the sound processor portion 110 may alternatively be locatedinternal to the patient.

The microphone 140 of FIG. 1 is configured to sense or detect audiosignals and convert the sensed signals into corresponding electricalsignals. In some examples, the audio signal may include speech. Theaudio signal may additionally or alternatively include music, noise,and/or other sounds. The electrical signals are sent to the soundprocessing unit 130 over an electrical or other suitable link.Alternatively, the microphone 140 may be connected directly to, orintegrated with, the sound processing unit 130.

The sound processing unit 130 may include any combination of hardware,software, and/or firmware as may serve a particular application. Forexample, the sound processing unit 130 may include one or moreprocessors, digital signal processors (“DSPs”), filters, programmablememory units, storage mediums, etc.

In some examples, the sound processing unit 130 may be configured toprocess the converted audio signals in accordance with a selected soundprocessing strategy to generate one or more control signals. Thesecontrol signals are configured to direct the implantable cochlearstimulator 150 to generate one or more electrical stimulation pulses tobe applied to one or more stimulation sites within a patient, as will bedescribed in more detail below.

The sound processing unit 130 shown in FIG. 1 may include or beimplemented within one or more devices configured to be worn orotherwise accessed by a patient. For example, the sound processing unit130 may include or be implemented within a behind-the-ear (“BTE”) soundprocessor configured to be positioned behind the ear. Alternatively, thesound processing unit 130 may include or be implemented within aportable speech processor (“PSP”) device, a conventional hearing aid, orany other type of sound processing unit.

The electrode lead 160 shown in FIG. 1 is configured to be insertedwithin a duct of a cochlea. As shown in FIG. 1, the electrode lead 160includes a plurality of electrodes 170, e.g., sixteen electrodes, spacedalong its length. It will be understood, however, that any number ofelectrodes 170 may be disposed on the electrode lead 160.

Electronic circuitry within the implantable cochlear stimulator 150 isconfigured to generate and apply electrical stimulation to one or morestimulation sites within the cochlea via selected stimulation channels(i.e., pairs or groups of the individual electrodes 170) in accordancewith one or more control signals generated by the sound processing unit130. Hence, as will be described in more detail below, one or moreelectrode leads 160 with one or more electrodes 170 disposed thereon maybe implanted within a patient such that the electrodes 170 are incommunication with one or more stimulation sites within the patient. Asused herein, the term “in communication with” refers to the electrodes170 being adjacent to, in the general vicinity of, in close proximityto, directly next to, or directly on the stimulation site.

One or more components of cochlear implant system 100 may be implantedwithin a patient's body while one or more components of cochlear implantsystem 100 may be located external to the patient. For example, theimplantable cochlear stimulator 150 and lead 160 may be implanted withinthe patient while the sound processing unit 130 and the microphone 140are configured to be located outside the patient, e.g., behind the ear.Hence, the implantable cochlear stimulator 150 and the sound processingunit 130 may be transcutaneously coupled via a suitable data orcommunications link 180. The communications link 180 allows power andcontrol signals to be sent from the sound processing unit 130 to theimplantable cochlear stimulator 150. In some embodiments, data andstatus signals may also be sent from the implantable cochlear stimulator150 to the sound processing unit 130.

The external and implantable portions of the cochlear implant system 100may each include one or more coils configured to transmit and receivepower and/or control signals via the data link 180. For example, theexternal portion 110 of the cochlear implant system 100 may include anexternal coil 190 and the implantable portion of the cochlear implantsystem 120 may include an implantable coil 195. The external coil 190and the implantable coil 195 may be inductively coupled to each other,thereby allowing data and power signals to be wirelessly transmittedbetween the external portion and the implantable portion of the cochlearimplant system 100.

FIG. 2 is a functional block diagram of an exemplary sound processingunit 130 and implantable cochlear stimulator 150. The functions shown inFIG. 2 are merely representative of the many different functions thatmay be performed by sound processing unit 130 and/or implantablecochlear stimulator 150. One or more of the functions may be performedin accordance with one or more of the control parameters describedherein.

As shown in FIG. 2, the microphone 140 senses an audio signal, such asspeech or music, and converts the audio signal into an electricalsignal. The electrical signal is then amplified with audio front-end(“AFE”) circuitry 210. The amplified signal is converted to a digitalsignal by an analog-to-digital (“A/D”) converter 220. The resultingdigital signal is subjected to automatic gain control using a suitableautomatic gain control (“AGC”) function 230.

After appropriate automatic gain control, the digital signal is thenprocessed in one of a number of digital signal processing or analysischannels 240. For example, the sound processing unit 130 may include,but is not limited to, eight analysis channels 240. Each analysischannel 240 may respond to a different frequency band of the sensedaudio signal due to a series of band pass filters 250.

As shown in FIG. 2, each of the m analysis channels 240 may also includean energy detection stage (D1-Dm) 255. Each energy detection stage 255may include any combination of circuitry configured to detect the amountof energy contained within each of the m analysis channels 240. Forexample, each energy detection stage 260 may include a rectificationcircuit followed by an integrator circuit.

As shown in FIG. 2, the signals within each of the analysis channels 240may be processed by a noise reduction facility 260. Noise reductionfacility 260 may include any combination of hardware and software andmay be configured to apply one or more noise reduction functions to oneor more of the signals within the analysis channels 240. For example,noise reduction facility 260 may be configured to increase asignal-to-noise ratio within one or more of the analysis channels 240.Noise reduction facility 260 will be described in more detail below.

Mapping stage 270 may be configured to map the signals in each of the manalysis channels 240 to one or more of M stimulation channels 290. Inother words, the information contained in the m analysis channels 240 isused to define the electrical stimulation pulses that are applied to thepatient by the implantable cochlear stimulator 150 via the M stimulationchannels 290. As mentioned previously, pairs or groups of individualelectrodes 170 may make up the M stimulation channels 290.

In some examples, the mapped signals are serialized by a multiplexer 280and transmitted to the implantable cochlear stimulator 150. Theimplantable cochlear stimulator 150 may then apply electricalstimulation via one or more of the M stimulation channels 290 to one ormore stimulation sites within the duct of the patient's cochlea. As usedherein, the term “stimulation site” will be used to refer to a targetarea or location to which the electrical stimulation is applied. Forexample, a stimulation site may refer to any location within a region ofauditory nerve tissue.

FIG. 3 illustrates a schematic structure of the human cochlea 300. Asshown in FIG. 3, the cochlea 300 is in the shape of a spiral beginningat a base 310 and ending at an apex 320. Within the cochlea 300 residesauditory nerve tissue 330, which is denoted by Xs in FIG. 3. Theauditory nerve tissue 330 is organized within the cochlea 300 in atonotopic manner. Low frequencies are encoded at the apex 320 of thecochlea 300 while high frequencies are encoded at the base 310. Hence,each location along the length of the cochlea 300 corresponds to adifferent perceived frequency. A cochlear prosthesis may therefore beimplanted within a patient with sensorineural hearing loss andconfigured to apply electrical stimulation to different locations withinthe cochlea 300 to provide the sensation of hearing. For example, theelectrode lead 114 may be disposed within the cochlea 300 such that theelectrodes 170 are in communication with auditory nerve tissue 330within the cochlea 300. Electrical stimulation may be applied by theelectrodes 170 to the auditory nerve tissue 330.

The sound processing unit 130 and the implantable cochlear stimulator150 may be configured to operate in accordance with one or more controlparameters. These control parameters may include one or more stimulationparameters governing the electrical stimulation generated by theimplantable cochlear stimulator 150, operating parameters, and/or anyother parameter as may serve a particular application. As mentioned,exemplary control parameters include, but are not limited to, volumecontrol parameters, noise reduction parameters, microphone sensitivityparameters, microphone direction parameters, pitch parameters, timbreparameters, sound quality parameters, most comfortable current levels(“M levels”), threshold current levels, channel acoustic gainparameters, front and backend dynamic range parameters, current steeringparameters, pulse rate values, pulse width values, frequency parameters,amplitude parameters, waveform parameters, electrode polarity parameters(i.e., anode-cathode assignment), location parameters (i.e., whichelectrode pair or electrode group receives the stimulation current),stimulation type parameters (i.e., monopolar, bipolar, or tripolarstimulation), burst pattern parameters (e.g., burst on time and burstoff time), duty cycle parameters, spectral tilt parameters, filterparameters, and dynamic compression parameters. Many other controlparameters may be specified as may serve a particular application.

In some examples, it is desirable to facilitate manual adjustment of oneor more control parameters governing the operation of the soundprocessing unit 130 and/or the implantable cochlear stimulator 150. Inthis manner, one or more control parameters may be adjusted by a user(e.g., the cochlear implant patient) to levels suitable for a particularpatient. To this end, a user input facility may be provided andconfigured to be selectively associated with one or more controlparameters in order to facilitate manual adjustment of the one or morecontrol parameters. As will be described in more detail below, the userinput facility may be communicatively coupled to at least one of thesound processing unit 130 and the implantable cochlear stimulator 150.

FIG. 4 illustrates an exemplary configuration of cochlear implant system100 wherein sound processing unit 130 includes a user input facility 400configured to facilitate manual adjustment of one or more controlparameters. User input facility 400 may include any combination ofhardware and software. For example, the user input facility 400 mayinclude a control dial or knob, one or more input keys, a graphical userinterface, and/or any other mechanism, software application, or deviceas may serve a particular application.

User input facility 400 shown in FIG. 4 may be communicatively coupledto one or more components of sound processing unit 130 in order tofacilitate manual adjustment of one or more control parameters governingthe operation of sound processing unit 130 and/or implantable cochlearstimulator 150. For example, as will be described in more detail below,user input facility 400 may be communicatively coupled to noisereduction facility 260 in order to facilitate manual adjustment of oneor more noise reduction parameters associated with an audio signal. Itwill be recognized that user input facility 400 may be additionally oralternatively coupled to any other component within sound processingunit 130 and/or implantable cochlear stimulator 150 as may serve aparticular application.

FIG. 5 shows an exemplary implementation 500 of the cochlear implantsystem 100 of FIG. 4 wherein sound processing unit 130 includes a BTEsound processor 510. As shown in FIG. 5, the user input facility 400 maybe implemented as a control dial 520 disposed at least partially on anouter surface of the BTE sound processor 510. The control dial 520 maybe rotated or otherwise adjusted by a patient or other use to adjust oneor more control parameters associated with the BTE sound processor 510and/or the implantable cochlear stimulator 150. For example, the controldial 520 may be rotated in a clockwise direction to increase a volumelevel associated with an audio signal, increase an amount of noisereduction applied to an audio signal, and/or adjust any other controlparameter as may serve a particular application. Likewise, the controldial 520 may be rotated in a counter-clockwise direction to decrease avolume level associated with an audio signal, decrease an amount ofnoise reduction applied to an audio signal, and/or adjust any othercontrol parameter as may serve a particular application.

While a control dial 520 is shown in FIG. 5, it will be recognized thatuser input facility 400 may be alternatively implemented within BTEsound processor 510 in any other manner as may serve a particularapplication. For example, user input facility 400 may include one ormore selectable buttons disposed on an outer surface of the BTE soundprocessor 510, one or more levers, and/or any other user input mechanismas may serve a particular application.

FIG. 6 illustrates an alternative implementation 600 of the cochlearimplant system 100 of FIG. 4 wherein the sound processing unit 130includes a PSP 610. As shown in FIG. 6, the user input facility 400 maybe implemented as a control dial 620 disposed at least partially on anouter surface of the PSP 610. The control dial 620 may be rotated orotherwise adjusted by a patient or other user to adjust one or morecontrol parameters associated with the PSP 610 and/or the implantablecochlear stimulator 150. For example, the control dial 620 may berotated in a clockwise direction to increase a volume level associatedwith an audio signal, increase an amount of noise reduction applied toan audio signal, and/or adjust any other control parameter as may servea particular application. Likewise, the control dial 620 may be rotatedin a counter-clockwise direction to decrease a volume level associatedwith an audio signal, decrease an amount of noise reduction applied toan audio signal, and/or adjust any other control parameter as may servea particular application.

FIG. 7 illustrates an alternative cochlear implant system 700 that maybe used in accordance with the systems and methods described herein. Asshown in FIG. 7, a remote control unit 710 may be communicativelycoupled to sound processing unit 130 and/or implantable cochlearstimulator 150 via one or more communication links (e.g., communicationlinks 720 and/or 730). Communication links 720 and 730 may include anytype of communication link as may serve a particular application. Forexample, communication links 720 and/or 730 may each include, but arenot limited to, a wireless communication link, an infrared link, a radiofrequency (“RF”) communication link, and/or any other type ofcommunication link as may serve a particular application.

Remote control unit 710 may include any type of device configured tocontrol the operation of sound processing unit 130 and/or implantablecochlear stimulator 150. For example, remote control unit 710 mayinclude a handheld device, a personal computer, a personal digitalassistant (“PDA”), a mobile phone, and/or any other device or apparatusas may serve a particular application. Remote control unit 710 mayinclude any suitable combination of hardware and software configured toperform the functions described herein.

As shown in FIG. 7, user input facility 400 may be included withinremote control unit 710 in order to facilitate manual adjustment of oneor more control parameters with remote control unit 710. The user inputfacility 400 may include a control dial, one or more buttons, and/or anyother user input facility as may serve a particular application.

While various implementations of user input facility 400 have been givenherein, it will be recognized that each of the implementations is merelyillustrative of the many different implementations of user inputfacility 400 that may be used in accordance with the systems and methodsdescribed herein. For example, in some implementations, user inputfacility 400 may include multiple user input facilities 400 eachconfigured to facilitate adjustment of a distinct control parameter. Toillustrate, the BTE sound processor 510 and/or the PSP 610 describedherein may each include two or more user input facilities 400 eachconfigured to facilitate adjustment of a distinct control parameter.

In some examples, user input facility 400 is configured to beselectively associated with one or more control parameters. In otherwords, user input facility 400 may be initially associated with aparticular control parameter and then subsequently associated withanother control parameter. In this manner, a patient may utilize thesame user input facility 400 to adjust more than one control parameter.For example, the user input facility 400 may be initially associatedwith a first control parameter (e.g., a volume level associated with anaudio signal), thereby allowing a patient to manually adjust the firstcontrol parameter. The user input facility 400 may then be selectivelydisassociated with the first control parameter and associated with asecond control parameter (e.g., a noise reduction parameter associatedwith the audio signal), thereby allowing the patient to manually adjustthe second control parameter. In some examples, sound processing unit130 and/or remote control unit 710 may be configured to perform theselective association of one or more control parameters with user inputfacility 400.

For example, sound processing unit 130 may be configured to associate acontrol parameter with user input facility 400 in accordance with aparticular “program” in which the sound processing unit 130 isconfigured to operate. In this manner, when sound processing unit 130switches to a different program, the control parameter associated withthe user input facility 400 may be changed or otherwise updated. Soundprocessing unit 130 may be configured to operate within any number ofprograms. Exemplary programs include, but are not limited to, a “normal”program wherein the sound processing unit 130 is configured to operatein accordance with one or more default control parameters, a “noisereduction” program wherein the sound processing unit 130 is configuredto operate in accordance with one or more noise reduction parameters,and/or any other mode of operation as may serve a particularapplication.

In some examples, a patient may manually switch between differentoperating programs of the sound processing unit 130. For example, FIG. 8shows an exemplary implementation 800 of cochlear implant system 100wherein sound processing unit 130 includes a program selection facility810. Program selection facility 810 may include any combination ofhardware and software and may be configured to facilitate manual and/orautomatic selection of one or more programs in which sound processingunit 130 may operate. To this end, program selection facility 810 may becommunicatively coupled to processing circuitry within sound processingunit 130 and configured to direct the processing circuitry to switchfrom operating in accordance with a particular program to operating inaccordance with another program (e.g., process an audio signal inaccordance with the other program). While program selection facility 810is shown to be included within sound processing unit 130, it will berecognized that program selection facility 810 may additionally oralternatively be included within remote control unit 710 or any otherdevice as may serve a particular application.

FIG. 9 illustrates an exemplary implementation 900 of cochlear implantsystem 800 wherein program selection facility 810 includes a programswitch 910 at least partially disposed on an outer surface of BTE soundprocessor 510. Program switch 910 may be accessed by a patient and usedto switch between different operating programs. For example, programswitch 910 may be configured to be selectively positioned at one of twopositions. Each position corresponds to a particular program. Forexample, a first position may correspond to a “normal” program whereinthe sound processing unit 130 is configured to operate in accordancewith one or more default control parameters. A second position maycorrespond to a “noise reduction” program, wherein sound processing unit130 may be configured to operate in accordance with one or more noisereduction parameters.

In some alternative examples, sound processing unit 130 may beconfigured to automatically switch between operating programs andthereby automatically change the particular control parameter that isassociated with user input facility 400. For example, sound processingunit 130 may be configured to switch between operating programs inresponse to a sensed listening environment or other factor. Toillustrate, sound processing unit 130 may be configured to detect whenthe user enters a noisy environment and automatically switch to a “noisereduction” program so that a patient may utilize user input facility 400to manually adjust one or more noise reduction parameters correspondingto an audio signal. It will be recognized that sound processing unit 130may be configured to automatically switch to any other operating programas may serve a particular application.

As mentioned, a control parameter may be selectively associated withuser input facility 400 in accordance with a particular program in whichsound processing unit 130 is configured to operate. For example, avolume control parameter may be associated with user input facility 400when sound processing unit 130 is configured to operate in accordancewith a “normal” program. In this manner, a patient may utilize the userinput facility 400 to manually adjust a volume level associated with anaudio signal while the sound processing unit 130 is operating within the“normal” program. When the sound processing unit 130 switches to anotherprogram, the control parameter associated with the user input facility400 may correspondingly change. For example, if the sound processingunit 130 switches to a “noise reduction” program, a noise reductionparameter may be selectively associated with the user input facility 400so that the user may manually adjust a noise reduction level associatedwith the audio signal. It will be recognized that any other controlparameter may be selectively associated with user input facility 400 asmay serve a particular application.

An example of how user input facility 400 may be used to manually adjustone or more noise reduction parameters associated with an audio signalwill now be given in connection with FIG. 10. As mentioned, soundprocessing unit 130 may include a noise reduction facility 260configured to increase a signal-to-noise ratio within one or moreanalysis channels 240. Noise reduction facility 260 may be configured tooperate in accordance with a noise reduction gain function. FIG. 10illustrates an exemplary noise reduction gain function 1000 that may beused by noise reduction facility 260 to increase a signal-to-noise ratiowithin one or more of the analysis channels 240.

As shown in FIG. 10, noise reduction facility 260 may be configured toapply gain to each of the analysis channels 240 depending on thesignal-to-noise ratios in each of the analysis channels 240. Forexample, if a signal-to-noise ratio within a particular analysis channel240 is equal to zero, noise reduction facility 260 may be configured toapply −10 dB gain to that channel. However if the signal-to-noise ratiowithin a particular analysis channel 240 is already equal to or greaterthan 10, noise reduction facility 260 does not apply any gain to thatchannel. By applying a negative amount of gain within a particularanalysis channel 240, the signal-to-noise ratio within the channel maybe increased.

Hence, by adjusting user input facility 400, a user may manually adjustthe amount of gain or noise reduction that is applied to one or more ofthe analysis channels 240. For example, if a user desires to increasethe amount of noise reduction that is applied to a particular audiosignal, the user may adjust user input facility 400 accordingly (e.g.,rotate control dial 520 in a clockwise direction). Likewise, if thepatient desires to decrease the amount of noise reduction that isapplied to a particular audio signal, the user may adjust the user inputfacility 400 accordingly (e.g., rotate control dial 520 in acounter-clockwise direction). In response to a detected interaction ofthe user with user input facility 400, sound processing unit 130 mayadjust a noise parameter (e.g., an amount of gain or noise reductionapplied to one or more analysis channels 240) accordingly.

While the examples given herein have illustrated how a volume controlparameter and/or one or more noise reduction parameters may beselectively associated with user input facility 400, it will berecognized that any of the other control parameters described herein maybe additionally or alternatively associated with user input facility400. For example, a patient may desire to manually adjust a sensitivityof microphone 140. In this instance, the patient may direct soundprocessing unit 130 to selectively associate a microphone sensitivityparameter with user input facility 400 (e.g., by selecting a predefinedprogram with program selection facility 840 or in any other suitablemanner). Once the association is established, adjustment of user inputfacility 400 may result in an adjustment of the sensitivity of themicrophone 140.

Another exemplary control parameter that may be associated with userinput facility 400 to facilitate manual adjustment thereof is a“stimulation type” control parameter. By adjusting the stimulation type,the patient may direct implantable cochlear stimulator 150 to applydifferent types of stimulation to one or more stimulation sites withinthe cochlea. For example, the implantable cochlear stimulator 150 may beselectively directed to apply monopolar, bipolar, or tripolarstimulation to one or more stimulation sites within the cochlea. Userinput facility 400 may additionally or alternatively be used to adjustan amount of compensation current applied to one or more electrodes 170designated as compensating electrodes during bipolar and/or tripolarstimulation.

FIG. 11 illustrates an exemplary method of facilitating manualadjustment of one or more control parameters governing an operation of asound processing unit (e.g., sound processing unit 130) and/or animplantable cochlear stimulator (e.g., implantable cochlear stimulator150). While FIG. 11 illustrates exemplary steps according to oneembodiment, other embodiments may omit, add to, reorder, and/or modifyany of the steps shown in FIG. 11. It will be recognized that any of thecomponents described herein may perform one or more of the steps shownin FIG. 11. For example, one or more of the steps shown in FIG. 11 maybe performed by sound processing unit 130.

In step 1102, an audio signal is processed in accordance with aplurality of control parameters. The audio signal may be processed inany of the ways described herein. The plurality of control parametersmay include any of the control parameters described herein.

In step 1104, an implantable cochlear stimulator is directed to applyelectrical stimulation representative of the audio signal to a patientvia one or more electrodes. The implantable cochlear stimulator may bedirected to apply the electrical stimulation in any of the waysdescribed herein.

In step 1106, a user input facility may be initially associated with afirst control parameter included in the plurality of control parametersin order to facilitate manual adjustment of the first control parameter.The association may be performed by sound processing unit 130 in any ofthe ways described herein. Alternatively, the association may beperformed by remote control unit 710.

In step 1108, the user input facility is selectively disassociated withthe first control parameter and associated with a second controlparameter in order to facilitate manual adjustment of the second controlparameter. The disassociation and association may be performed by soundprocessing unit 130 and/or remote control unit 710 in any of the waysdescribed herein.

The preceding description has been presented only to illustrate anddescribe embodiments of the invention. It is not intended to beexhaustive or to limit the invention to any precise form disclosed. Manymodifications and variations are possible in light of the aboveteaching.

What is claimed is:
 1. A system comprising: a sound processing unitconfigured to process an audio signal and to selectively operate inaccordance with a first program or a second program; an implantablecochlear stimulator communicatively coupled to the sound processing unitand configured to apply stimulation representative of the audio signalto a patient via one or more electrodes in accordance with theprocessing of the audio signal, the sound processing unit and theimplantable cochlear stimulator being configured to operate inaccordance with a plurality of control parameters; and a user inputfacility communicatively coupled to the sound processing unit andconfigured to be initially associated with a first control parameterincluded in the plurality of control parameters while the soundprocessing unit operates in accordance with the first program in orderto facilitate manual adjustment of the first control parameter; and aprogram switch communicatively coupled to the sound processing unit andconfigured to direct the sound processing unit to switch from operatingin accordance with the first program to operating in accordance with thesecond program; wherein the user input facility is further configured tobe selectively disassociated with the first control parameter andassociated with a second control parameter included in the plurality ofcontrol parameters in response to the program switch directing the soundprocessing unit to switch from operating in accordance with the firstprogram to operating in accordance with the second program in order tofacilitate manual adjustment of the second control parameter.
 2. Thesystem of claim 1, wherein the user input facility comprises a controldial.
 3. The system of claim 1, wherein the user input facility is atleast partially disposed on an outer surface of the sound processingunit.
 4. The system of claim 1, further comprising a remote control unitcommunicatively coupled to at least one of the sound processing unit andthe implantable cochlear stimulator, wherein the user input facility isincluded in the remote control unit.
 5. The system of claim 1, whereinthe sound processing unit is configured to adjust at least one of thefirst and second control parameters in response to interaction of a userwith the user input facility.
 6. The system of claim 5, wherein the userinput facility comprises a control dial, and wherein the interaction ofthe user with the user input facility comprises a rotation of thecontrol dial by the user.
 7. The system of claim 1, wherein: the programswitch is further configured to direct the sound processing unit toswitch from operating in accordance with the second program back tooperating in accordance with the first program; and the user inputfacility is further configured to be selectively disassociated with thesecond control parameter and re-associated with the first controlparameter in response to the sound processing unit switching fromoperating in accordance with the second program back to operating inaccordance with the first program.
 8. The system of claim 1, wherein theprogram switch is further configured to sense a listening environment ofthe patient and automatically direct the sound processing unit to switchfrom operating in accordance with the first program to operating inaccordance with the second program in accordance with the sensedlistening environment.
 9. The system of claim 1, wherein the programswitch is further configured to direct the sound processing unit toswitch from operating in accordance with the first program to operatingin accordance with the second program in response to interaction of auser with the program switch.
 10. The system of claim 1, wherein theplurality of control parameters comprise at least two of a noisereduction parameter associated with the audio signal, a volume parameterassociated with the audio signal, a microphone direction parameter, amicrophone sensitivity parameter, a compensation current parameter, astimulation type parameter, a pitch parameter, a timbre parameter, asound quality parameter, a most comfortable current level, a thresholdcurrent level, a channel acoustic gain parameter, a dynamic rangeparameter, a current steering parameters, a pulse rate value, a pulsewidth value, a frequency parameter, an amplitude parameter, a waveformparameter, an electrode polarity parameter, a location parameter, aburst pattern parameter, a duty cycle parameter, a spectral tiltparameter, a filter parameter, and a dynamic compression parameter. 11.The system of claim 1, wherein the first control parameter comprises avolume parameter corresponding to the audio signal and the secondcontrol parameter comprises a noise reduction parameter corresponding tothe audio signal.
 12. A method comprising: processing, by a soundprocessing unit, an audio signal in accordance with a plurality ofcontrol parameters; directing, by the sound processing unit, animplantable cochlear stimulator to apply electrical stimulationrepresentative of the audio signal to a patient via one or moreelectrodes; initially associating, by the sound processing unit, a userinput facility with a first control parameter included in the pluralityof control parameters in order to facilitate manual adjustment of thefirst control parameter while the sound processing unit operates inaccordance with a first program; switching, by the sound processingunit, from operating in accordance with the first program to operatingin accordance with a second program; selectively disassociating, by thesound processing unit in response to the sound processing unit switchingfrom operating in accordance with the first program to operating inaccordance with the second program, the user input facility with thefirst control parameter and associating the user input facility with asecond control parameter in order to facilitate manual adjustment of thesecond control parameter.
 13. The method of claim 12, furthercomprising: detecting, by the sound processing unit, an interaction of auser with the user input facility; adjusting, by the sound processingunit, the second control parameter in response to the detectedinteraction of the user with the user input facility.